Hall thruster is a type of electrostatic electric propulsion device, and it is used to carry out spacecraft attitude and orbit maneuvers.
Hall thrusters have high thrust density/efficiency, reliable/robust operation, simple design, and extensive space flight heritage. These main features make them attractive candidates for small/micro satellite applications. Scaling-down these devices to low power levels is quite a challenge because of the large surface area to volume, and the physical limits to the magnetic circuit miniaturization. Besides, scaling-down the thruster channel geometry results in short lifetime because of rapid erosion of thruster parts like discharge channel and magnetic pole piece, caused by increased plasma-wall interactions.
Plasma-wall interactions have substantial effects on discharge characteristics as well as on thruster performance. Power loss to the channel walls is the main power/efficiency loss source, and cause of erosion in conventional Hall thrusters. Therefore, development of low power Hall thrusters with longer lifetime remains an active area of research. My invention offers a radical solution to the scaling down and erosion problem of Hall thrusters by producing and sustaining plasma discharge completely outside a cavity.